References:
- Maternal & Child Health Nursing: Care of the childbearing & childrearing family, 8th Edition, ISBN 978-1-4963-4813-5, by JoAnne Silbert-Flagg and Adele Pillitteri (Ch. 21)
Multiple gestation is considered a complication of pregnancy because a woman’s body must adjust to the effects of more than one fetus. The incidence of multiple births has increased dramatically because of the use of in vitro fertilization, but still only occurs in 2% to 3% of all births.
- Identical (i.e., monozygotic) twins begin with a single ovum and spermatozoon. In the process of fusion, or in one of the first cell divisions, the zygote divides into two identical individuals. Single-ovum twins usually have one placenta, one chorion, two amnions, and two umbilical cords. The twins are always of the same sex; they account for one third of twin births.
- The other two thirds of twins are fraternal (i.e., dizygotic, nonidentical), the result of the fertilization of two separate ova by two separate spermatozoa (possibly not from the same sexual partner). Double-ova twins have two placentas, two chorions, two amnions, and two umbilical cords. The twins may be of the same or a different sex. It is sometimes difficult to determine by ultrasound or at birth whether twins are identical or fraternal because the two fraternal placentas may fuse and appear as one large placenta.
Multiple pregnancies of two to eight children may be single-ovum conceptions, multiple-ova conceptions, or a combination of the two types. Most multiple pregnancies today occur from multiple ova being implanted as an in vitro fertility process. Naturally occurring multiple pregnancies are more frequent in Blacks and Hispanics than Whites. The higher a woman’s parity and age, the more likely she is to have a multiple gestation. Inheritance appears to play a role in natural dizygotic twinning; this has a familial maternal pattern of occurrence.
Assessment
Multiple gestation is suspected early in pregnancy when the uterus begins to increase in size at a rate faster than usual. AFP levels will also be elevated. At the time of quickening, a woman report flurries of action at different portions of her abdomen rather than at one consistent spot (e.g., where the feet are located). On auscultation of the abdomen, multiple sets of fetal heart sounds can be heard; although if one or more fetus has his or her back positioned toward a woman’s back, only one fetal heart sound may be heard.
Vanishing Twin Syndrome
An ultrasound can reveal multiple gestation sacs early in pregnancy. In some instances, early ultrasound examinations reveal multiple amniotic sacs but then later in pregnancy, in as many as 30% of women, only one fetus remains (i.e., vanishing twin syndrome). Women who were told they were having twins but then later in pregnancy find out they are having only one child may grieve for a vanished twin as much as if the baby had died at birth.
Therapeutic Management
Women with a multiple gestation are more susceptible to complications of pregnancy such as gestational hypertension, polyhydramnios, placenta previa, preterm labor, and anemia than are women carrying one fetus. Following birth, they are more prone to postpartum bleeding because of the additional uterine stretching that occurred.
- 25% of low-birth-weight babies are from multiple pregnancies because a multiple pregnancy usually ends before term.
- If monozygotic twins share a common vascular communication, it can lead to overgrowth of one fetus and undergrowth of the second (a twin-to-twin transfusion), resulting in discordant infants.
If a single amnion is present, there can be knotting and twisting of umbilical cords, causing fetal distress or difficulty with birth. Because of the possibility of these complications, a woman with a twin pregnancy needs closer prenatal supervision than a woman with a single gestation to detect these problems as early as possible. A woman carrying more than two fetuses is at greatest risk.
Nursing Diagnoses
- Fatigue related to increased stress on body functioning secondary to multiple gestation
- Parental role conflict related to recent discovery of multiple (as opposed to single) pregnancy
- Fear concerning her own and the babies’ health related to risks of a multiple pregnancy