Chorionic Villus Sampling (CVS) – 12 weeks
CVS is the withdrawal of a small sample of the placental tissue (chorionic villi) surrounding the fetus. CVS is performed transabdominally (with a needle inserted through the woman’s abdominal wall). Ultrasound is used to guide the needle to the appropriate location in the placenta and protect the fetus.
CVS involves a small risk to both the mother and the fetus. The most common serious complication is miscarriage. In general, the risk for a miscarriage from CVS is less than 1 in 300. Minor complications include cramping, vaginal spotting, or slight leakage of amniotic fluid. Limb defects have been reported in the past in patients having CVS prior to 9.5 weeks and mostly when the CVS was done through the vagina/cervix. No such defects have ever been reported in cases done abdominally and after 9 weeks but cannot be excluded with 100% certainty....
Any particular attempt to obtain chorionic villi may be unsuccessful. Occasionally, even if sufficient tissue is obtained, laboratory analysis may not be possible or may not yield results. In these cases repeat CVS or amniocentesis may be offered.
The standard laboratory testing performed on a sample of chorionic villi can usually detect a high percentage of all chromosome disorders. There is approximately a 1 in 100 chance that the CVS results will be uncertain due to placental problems (confined placental mosaicism). In these cases the sample may show a mixture of normal and abnormal cells, and amniocentesis may be suggested.
Normal test results do not guarantee the birth of a normal child. As in any laboratory test, there is a small possibility of error, and maternal cells may contaminate the sample. In addition, approximately 2-4% of all pregnancies have birth defects, which cannot be detected by testing the chorionic villi. Foetuses with normal chromosomes may still have anatomical defects as well as mental retardation.
You need to have restricted physical activity for 48 hours and shall be prescribed antibiotics and progesterone support after the procedure for 5 days.
Amniocentesis – 16 weeks
Amniocentesis is the withdrawal of a small sample (18-20 ml) of the fluid surrounding the fetus. This fluid is obtained by inserting a needle through the abdominal wall into the uterus (womb). Ultrasound is usually performed to help locate the placenta and the fetus. Amniocentesis involves a small risk to both the mother and the fetus. The most common serious complication is miscarriage. In general, the risk of miscarriage from amniocentesis performed after 16 weeks of pregnancy is less than 1 in 500. Other possible, but rare, serious complications include hemorrhage, infection or injury to the fetus. Minor complications, which occur in approximately 1 in 100 women having amniocentesis, include cramping, vaginal spotting, or slight leakage of amniotic fluid.
Any particular attempt to obtain amniotic fluid may be unsuccessful. Occasionally, even if sufficient fluid is obtained, laboratory testing may not be possible or may not yield results. In these cases, the amniocentesis may need to be repeated. The standard laboratory testing performed on the amniotic fluid sample consists of chromosome analysis, which can usually detect a high percentage of all chromosomal disorders. Testing for other kinds of birth defects will not be performed unless indicated below. Normal test results do not guarantee the birth of a normal child. As in any laboratory test, there is a small possibility of error, and maternal cells may contaminate the sample. In addition, approximately 2-3% of all pregnancies have birth defects which cannot be detected by testing amniotic fluid or by ultrasound examination. QFPCR / FISH (5 Probes) is a rapid test designed to detect the most common chromosome abnormalities, including Down syndrome, in samples of amniotic fluid. The test gives numeric information about chromosomes 13, 18, 21, X and Y. The test result are usually available 5 working days after the amniocentesis procedure. Other chromosome abnormalities are usually found by routine chromosome analysis. This usually take 18-19 days for results.
In 1-2% of cases, uninformative analysis of culture results are obtained. In some cases, this is because the maternal blood is in the amniotic fluid. In other cases the sample is a mosaic cell pattern for normal cell and abnormal cell.
In approximately 1% of cases, no culture results are obtained. In some cases this is because the amount of foetal cells in amniotic fluid sample is too small. In other cases, the test is attempted but does not give any results.
There is a small possibility that the culture results are different from the FISH / QFPCR results. QFPCR / FISH results are considered preliminary; therefore, no irreversible decision about a pregnancy should be made on the basis of these results alone. You need to have restricted physical activity for 48 hours and shall be prescribed antibiotics and progesterone support after the procedure for 5 days.
Amnio-Infusion – Oligohydramnios
Amnioinfusion - "Intrapartum Amnioinfusion"
Severe oligohydramnios: Amniotic fluid index (AFI) < 5 cm. To avoid the related complication; pulmonary hypoplasia, deforming effects of oligohydramnios, variable FHR decelerations and intraventricular haemorrhage. During labour, oligohydramnios could cause foetal distress due to compression of the umbilical cord. Antepartum amnioinfusion seems to increase the latency period between premature rupture of membranes and delivery
Aetiology: Premature rupture of membranes, congenital abnormalities of the urinary tract of the foetus, placental insufficiency, twin–twin transfusion syndrome, post-maturity, high maternal blood pressure
Functions: Normal AFI is essential for foetal movement and helping proper musculoskeletal, pulmonary, facial development; cushions the foetus from external forces. Procedure Under ultrasound guidance, 20 G spinal needle is inserted through the uterine wall into the amniotic cavity and isotonic fluid (normal saline) is infused until the volume of amniotic fluid is normalised. The procedure may be repeated if oligohydramnios recurs (serial amnioinfusion).
Amnio-Drainage – Polyhydramnios
Amnio-Drainage Polyhydramnios – (Deepest vertical pocket of amniotic fluid > 8 cm or AFI > 25 cm) has reported prevalence of 1-2%.
Polyhydramnios may have several obstetric reasons; foetal abnormalities, placental tumours, maternal diabetes mellitus, foetal anaemia, Twin – Twin Transfusion syndrome.
In 40-50% of cases no cause is evident prenatally and classified as idiopathic.
Most common complications within 48 hours are preterm birth (4.1%); preterm rupture of membranes (1.1%).
It is an established technique to improve maternal comfort and reduce the risks of severe polyhydramnios in both singleton and twin pregnancies, decreasing uterine contractility and over-stretching of membranes and uterus.
It also acts on the pathological processes of twin to twin transfusion syndrome.
Procedure: Under ultrasound guidance, 20 G spinal needle is inserted through the uterine wall into the amniotic cavity and the excess amount of amniotic fluid is drained slowly to normalise the AFI index to 50th centile for gestational age. The procedure may be repeated if polyhydramnios recurs (serial amnioreduction).
Amnio-PATCH – Premature Rupture of Membranes
Premature rupture of membranes (PROM) complicates approximately 10–12 % of pregnancies and may happen in 0.8–1 % postamniocentesis. Rate of foetal morbidity and mortality with PROM is very high due to preterm delivery, infection, miscarriage or pulmonary hypoplasia due to chronic oligohydramnios. Once the active infection subsides, signs of overt chorioamnionitis like fever, increased C reactive protein (CRP), white blood cells and uterine tenderness; after detailed informed counselling, the procedure of amniopatch is done.
Autologous platelet aphersis is done and aliquot of 30 mL are made.Under all aseptic conditions, 20 gauge spinal needle was inserted intra-amniotically; very slowly to avoid any foetal or umbilical cord injury, small quantity of amniotic fluid is aspirated and sent for culture and sensitivity.
There is infusion of platelets followed by cryoprecipitate; providing fibrinogen, fibronectin, platelet derived growth factors, TGF-beta, von Willebarnd factor, factor VIII and factor XIII in high concentrations, which helps in restoring the amniochorial link.
The entire transfusion takes around 15–20 min. Procedural success rate of amniopatch is 58%; with overall live birth rate of 68% and survival to discharge rate of 55%.
Multifetal Pregnancy Reduction
A procedure called multifetal reduction lowers the number of foetuses and improves your chances for a healthy pregnancy. Also called foetal reduction or selective pregnancy reduction, it’s a safe procedure, and chances of problems are small. Multiple pregnancies are more likely to miscarry or delivering prematurely. Premature delivery can cause problems with your babies' lungs, heart, stomach, and brain. They could also face lifelong health issues like cerebral palsy, intellectual disability, and vision and hearing loss.
Mothers who have multiple pregnancies are more prone for severe morning sickness; constipation; diabetes Preeclampsia (high blood pressure), anaemia; placental abruption.
Usually, the procedure happens during the first trimester (12 weeks) of your pregnancy; under ultrasound guidance. A small needle is inserted into your abdomen and then gently inject a special drug into a pouch. This medicine quickly stops the foetus’s heart.
Foetal pregnancy reduction takes only a few minutes.
Potential Problems and Aftercare
Infections from foetal reduction are rare; a small number of women can miscarry after the procedure (the risk for a miscarriage from MFPR is less than 1 in 500) or go into preterm labour.
Spontaneous resumption of cardiac activity after achievement of cardiac asystole has been reported in 1% of the cases; needing to repeat the MFPR procedure. You need to have restricted physical activity for 48 hours and shall be prescribed antibiotics and progesterone support after the procedure for 5 days.
Scar Ectopic Pregnancy Reduction – Pregnancy Implanting in LSCS Scar
Scar Ectopic Pregnancy Reduction
Caesarean scar pregnancy (CSP) - Gestational sac is fully or partially implanted within previous caesarean section scar; occurs in approximately 1 in 2000 pregnancies.
Rising incidence due to increase in primary & repeat caesarean sections
Also has been reported following myomectomy, uterine evacuation, previous abnormally adherent placentation, manual removal of placenta, metroplasty, hysteroscopy, and in vitro fertilization.
Endometrial and myometrial disruption or scarring predispose for abnormal pregnancy implantation.
Implanting blastocyst invades through a microscopic tract formed by the trauma of an earlier caesarean scar.
Routine surgical evacuation (misdiagnosed) may lead to major haemorrhage resulting in hysterectomy.
Local injection and scar ectopic pregnancy reduction
Local injection of methotrexate; gestational sac is aspirated and methotrexate injected under ultrasound guidance.
Foetal Autopsy (Perinatal Autopsy)
Foetal Autopsy (Perinatal Autopsy)
Examination of the foetus / baby after delivery; in circumstances where there is uncertainty about the precise cause of death, a perinatal autopsy and pathological examination often provides helpful clinical information.
It is helpful in the management of the subsequent pregnancy.
In approximately one third of “unexplained” stillbirths, an post-mortem examination reveals an explanation for the death.
It is helpful in identifying additional findings in 22% to 76% of cases; leading to confirmation of clinical findings or change in diagnosis. It is very helpful in ascertaining the cause of death or for counselling for future pregnancies.
Foetal Shunt Procedures
Pleural-amniotic shunt for foetal pleural effusion
Isolated foetal pleural effusions are more commonly unilateral and may be bilateral. They arise due to congenital malformations, chromosomal abnormalities, chylothorax, anaemia, heart defects, cardiac arrhythmias, and viral infections. It may prevent normal lung growth and development; large effusions may have pressure effects; venacaval compression, leading to hydrops. If prolonged may cause pulmonary hypoplasia, with respiratory failure in postnatal period.
Some pleural effusions may resolve spontaneously Large effusions producing respiratory compromise with or without pulmonary hypoplasia require immediate drainage. Pre-natal interventions include thoracocentesis and drainage of the effusions in an attempt to allow normal lung development and prevention of hydrops. If the fluid re-accumulates it requires repeated procedures.
Initial treatment involves needle aspiration drainage from the foetal chest cavity along with amniocentesis to establish an underlying aetiology. In case of fluid reaccumulation; shunting is considered. It involves insertion of a double pigtail catheter though the foetal pleural cavity to the amniotic cavity, allowing continued drainage of fluid from the pleural cavity into the amniotic fluid.
Foetal vesicoamniotic shunt for lower urinary tract outflow obstruction
In cases of feotal lower urinary tract outflow obstruction; urethral atresia, posterior urethral valves. Severe obstruction leads to oligohydramnios; both pulmonary and/or renal dysplasia. Pulmonary and/or renal dysplasia may detrimental and the baby may have respiratory or renal failure in immediate new-born period, requiring ventilatory support and/or renal dialysis or kidney transplantation.
Foetal vescico-amniotic shunt for lower urinary tract outflow obstruction aims to decompress the obstructed foetal bladder and restore amniotic fluid and preventing oligohydramnios and pulmonary and/or renal hypoplasia. It has to be done before the critical stages of lung and renal development so as to avoid permanent lung and kidney damage.
Foetal chromosomal analysis is usually performed before the procedure, to diagnose or exclude concomitant chromosomal abnormalities. It involves insertion of a double pigtail catheter; one end into the bladder and the other in the amniotic cavity; allowing continued drainage of fluid from the bladder cavity into the amniotic fluid.
Intrauterine Blood Transfusion (IUT)
Haemolytic disease of the foetus is caused by maternal alloantibodies that cross to the foetal circulatory system and cause haemolysis. It leads to foetal anaemia, hydrops fetalis and may ultimately result in intrauterine foetal death (IUFD).
Intrauterine transfusion (IUT) was first introduced in 1963; and from then, the procedure has improved to umbilical vein transfusion under constant ultrasonographic guidance. Intrauterine blood transfusions (IUTs) are performed using an ultrasound-guided needle inserted into the umbilical vein and treatment of foetal anaemia. Survival rates are in excess of 90%.
Main indication for an IUT is foetal anaemia due to RBC alloimmunisation, any foetal disease with severe anaemia, parvovirus B19 infections and massive fetomaternal haemorrhage. The risk of foetal loss is around 1-2%.
Risk factors for severe foetal anaemia include: relevant obstetric history, presence of maternal red blood cell antibodies, ultrasound markers as cardio-, hepato- and splenomegaly and signs of hydrops and diminished foetal movements.
Timing of intra-uterine transfusion is guided by MCA PSV (middle cerebral artery peak systolic velocity) doppler measurement to predict severe foetal anaemia. It is a reliable diagnostic tool between 16 and 36 weeks gestation in experienced hands. In experienced hands, intrauterine transfusion is a safe and effective procedure to treat RBC-alloimmunization. Adverse events are mostly related to hydrops, so that timely referral and intervention remains mandatory.
Chorionic Villus Sampling (CVS) – 12 weeks