Normal amount of amniotic fluid for twins

If the pregnant woman is carrying twins, then at around 40 weeks of pregnancy, the amniotic fluid will be around 800 ml. If the pregnancy is overdue, the amniotic fluid will be significantly reduced. Generally speaking, pregnant women with twins should be checked in time to see whether the amniotic fluid is normal. Too much or too little amniotic fluid can be very harmful to the twins. Let's take a look at this aspect.

Normal amount of amniotic fluid for twins

At 8 weeks of pregnancy, the amount of amniotic fluid is 5-10 ml, at 10 weeks of pregnancy, it is about 30 ml, at 20 weeks of pregnancy, it is about 400 ml, at 38 weeks of pregnancy, it is about 1000 ml. After that, the amount of amniotic fluid gradually decreases, and at 40 weeks of pregnancy, it is about 800 ml. In post-term pregnancy, the amniotic fluid is significantly reduced and can be reduced to less than 300ml.

Causes of low amniotic fluid

1. In case of overdue pregnancy, the placenta functions poorly, the perfusion is insufficient, the fetus becomes dehydrated, and the amount of amniotic fluid is low. Some scholars also believe that in overdue pregnancy, the fetus is overmature, its renal tubules are more sensitive to antidiuretic hormone, and the low urine volume leads to oligohydramnios. The incidence of oligohydramnios caused by post-term pregnancy is as high as 20%-30%.

2. Fetal malformations, such as congenital renal agenesis, renal hypoplasia, ureteral or urethral stenosis, etc., lead to oliguria or anuria and cause oligohydramnios.

3. Intrauterine growth retardation (IUGR) Oligohydramnios is one of the characteristics of intrauterine growth retardation. Chronic hypoxia causes redistribution of fetal blood circulation, mainly supplying the brain and heart, while renal blood flow decreases and fetal urine production decreases, resulting in oligohydramnios.

4. Amniotic membrane lesions. Electron microscopic observations revealed that the amniotic epithelial layer becomes thinner when the amniotic fluid is too low, the epithelial cells atrophy, the microvilli are short and thick, the tips are swollen, the number is small, there is squamous metaplasia, the rough inner reticular tissue and Golgi complex in the cells are also reduced, and the desmosomes and hemidesmosomes between the epithelial cells and the basement membrane are reduced. It is believed that some unexplained oligohydramnios may be related to lesions of the amniotic membrane itself.

After a brief introduction by the editor, I believe you all have some understanding of the normal range of amniotic fluid depth in twins and the reasons for low amniotic fluid. During pregnancy, in the case of post-term pregnancy, the placenta functions poorly, the perfusion volume is insufficient, the fetus becomes dehydrated, and the amniotic fluid is low. I hope the above article can help pregnant mothers!