When multiple pregnancy is the development of more than one fetus.It may be associated with a single fertilization (identical twins, identical triplets, and so on. D.) Or more (fraternal twins, triplets and so trehyaytsevaya. D.) Eggs.In most cases, only one is fertilized egg, so only one embryo is formed.This happens because the monthly cycle one ovary is resting, while the other is the formation of a mature egg and ovulation.
There are two possibilities of such a pregnancy.In the first case, one fertilized egg and is divided into two or more embryos - twins called in case of identical or monozygotic.Children are born of the same sex, with identical genetic makeup and strikingly similar in appearance.If in a monthly cycle ripen several eggs are fertilized and they speak of multiple pregnancy with fraternal, more fraternal (dizygotic), children.The degree of external and genetic similarity in this case is the same as with other native brothers and sisters.
Women with multiple pregnancies are a
This type of pregnancy occurs much less frequently than that at which matures and is fertilized only one ovum.It is determined according to the formula Hellin: the number of pregnancies with twins is 1: n1 , triplets - 1: n2 , quadruplets - 1: n3 and so on. E., Where « n "means the proportion of all births in the study population.Scientists have not identified any external factors that might influence the development of multiple identical pregnancy.On the other hand, distinguish the circumstances that increase the probability of dizygotic multiple pregnancies.These include the use of drugs that stimulate the formation of eggs (e.g. during infertility treatment);Women over the age of 35 years;the birth of her earlier at least three children;multiple pregnancy in the past;pregnant woman who herself is one of twins;the recent renunciation of the use of contraceptives;belonging to the Negroid race.
How to recognize multiple pregnancy
diagnosis of multiple pregnancy is based on several principles.First of all, it confirms the suspicion that conception occurred more than one child and that the embryos develop normally.The next step - an attempt to determine the zygosity fruits: whether they are single - or mnogoyaytsevymi.Thus, parents know whether their children are different in appearance and genetically, or will be, in this sense identical.To do this, an ultrasound determines the number of the amnion (sac), the presence of amniotic partition number chorions (placenta).It should, inter alia, to analyze the types of mutual vascular connections in the placenta.The study should be repeated periodically.This is necessary because sometimes recorded the death and resorption of one of the twins, giving place to the development of a healthy and strong.Standards of medical monitoring of multiple pregnancy, in principle, no different from the reference singletons, with the only difference that should cover the care of two or more children in the womb of a woman.Sometimes it is a challenge to the gynecologist, especially in the case of any complications.
What can you expect, nurturing several children?Surely more weight gain and a greater waist circumference.With multiple pregnancy associated higher requirement for iron, vitamins and other essential components.Moreover, it should take into account the increased risk of preeclampsia (hypertension induced by pregnancy), premature birth and other complications.Multiple pregnancy, unfortunately, more often ends caesarean section.
The most common medical problems multiple pregnancy include premature birth;malposition;birth trauma;lack of oxygen;greater risk of perinatal death.