Complications of pregnancy


Complications of pregnancy are health problems that are related to pregnancy. Complications that occur primarily during childbirth are termed obstetric labor complications, and problems that occur primarily after childbirth are termed puerperal disorders. Severe complications of pregnancy, childbirth, and the puerperium are present in 1.6% of mothers in the US, and in 1.5% of mothers in Canada. In the immediate postpartum period, 87% to 94% of women report at least one health problem. Long-term health problems are reported by 31% of women.
In 2016, complications of pregnancy, childbirth, and the puerperium resulted globally in 230,600 deaths, down from 377,000 deaths in 1990. The most common causes of maternal mortality are maternal bleeding, Postpartum infections including maternal sepsis, hypertensive diseases of pregnancy, obstructed labor, and :Category:Pregnancy with abortive outcome|pregnancy with abortive outcome, which includes miscarriage, ectopic pregnancy, and elective abortion.
There is no clear distinction between complications of pregnancy and symptoms and discomforts of pregnancy. However, the latter do not significantly interfere with activities of daily living or pose any significant threat to the health of the mother or baby. Still, in some cases the same basic feature can manifest as either a discomfort or a complication depending on the severity. For example, mild nausea may merely be a discomfort, but if severe and with vomiting causing water-electrolyte imbalance it can be classified as a pregnancy complication.

Maternal problems

The following problems originate mainly in the mother.

Gestational diabetes

is when a woman without diabetes develops high blood sugar levels during pregnancy.

Hyperemesis gravidarum

is the presence of severe and persistent vomiting, causing dehydration and weight loss. It is more severe than the more common morning sickness and is estimated to affect 0.5–2.0% of pregnant individuals.

Pelvic girdle pain

Potential severe hypertensive states of pregnancy are mainly:
, a form of venous thromboembolism, has an incidence of 0.5 to 7 per 1,000 pregnancies, and is the second most common cause of maternal death in developed countries after bleeding.
Levels of hemoglobin are lower in the third trimesters. According to the United Nations estimates, approximately half of pregnant individuals suffer from anemia worldwide. Anemia prevalences during pregnancy differed from 18% in developed countries to 75% in South Asia.
Treatment varies due to the severity of the anaemia, and can be used by increasing iron containing foods, oral iron tablets or by the use of parenteral iron.

Infection

A pregnant woman is more susceptible to certain infections. This increased risk is caused by an increased immune tolerance in pregnancy to prevent an immune reaction against the fetus, as well as secondary to maternal physiological changes including a decrease in respiratory volumes and urinary stasis due to an enlarging uterus. Pregnant individuals are more severely affected by, for example, influenza, hepatitis E, herpes simplex and malaria. The evidence is more limited for coccidioidomycosis, measles, smallpox, and varicella. Mastitis, or inflammation of the breast occurs in 20% of lactating individuals.
Some infections are vertically transmissible, meaning that they can affect the child as well.

Peripartum cardiomyopathy

is decrease in heart function which occurs in the last month of pregnancy, or up to six months post-pregnancy. It increases the risk of congestive heart failure, heart arrhythmias, thromboembolism, and cardiac arrest.

Hypothyroidism

Hypothyroidism is an autoimmune disease that affects the thyroid in pregnant individuals. This condition can have a profound effect during pregnancy and on the child. The infant may be seriously affected and have a variety of birth defects. Many pregnant individuals with Hashimoto's disease develop an underactive thyroid. The clinician will do an exam and order one or more tests.

Fetal and placental problems

The following problems occur in the fetus or placenta, but may have serious consequences on the mother as well.

Ectopic pregnancy

is implantation of the embryo outside the uterus
is the loss of a pregnancy prior to 20 weeks. In the UK, miscarriage is defined as the loss of a pregnancy during the first 23 weeks.

Placental abruption

is the separation of the placenta from the uterus.
is when the placenta fully or partially covers the cervix.

Placenta accreta

is an abnormal adherence of the placenta to the uterine wall.

Multiple pregnancies

Multiples may become monochorionic, sharing the same chorion, with resultant risk of twin-to-twin transfusion syndrome. Monochorionic multiples may even become monoamniotic, sharing the same amniotic sac, resulting in risk of umbilical cord compression and entanglement. In very rare cases, there may be conjoined twins, possibly impairing function of internal organs.

Vertically transmitted infection

The embryo and fetus have little or no immune function. They depend on the immune function of their mother. Several pathogens can cross the placenta and cause infection. Often microorganisms that produce minor illness in the mother are very dangerous for the developing embryo or fetus. This can result in spontaneous abortion or major developmental disorders. For many infections, the baby is more at risk at particular stages of pregnancy. Problems related to perinatal infection are not always directly noticeable.
The term TORCH complex refers to a set of several different infections that may be caused by transplacental infection.
Babies can also become infected by their mother during birth. During birth, babies are exposed to maternal blood and body fluids without the placental barrier intervening and to the maternal genital tract. Because of this, blood-borne microorganisms, organisms associated with sexually transmitted disease, and normal fauna of the genito-urinary tract are among those commonly seen in infection of newborns.

Intrauterine bleeding

There have been rare but known cases of intrauterine bleeding caused by injury inflicted by the fetus with its fingernails or toenails.

General risk factors

Factors increasing the risk of pregnancy complications beyond the normal level of risk may be present in the pregnant individual's medical profile either before they become pregnant or during the pregnancy. These pre-existing factors may related to the individual's genetics, physical or mental health, their environment and social issues, or a combination of those.

Biological

Some common biological risk factors include:
Some common environmental risk factors include:
Some disorders and conditions can mean that pregnancy is considered high-risk and in extreme cases may be contraindicated. High-risk pregnancies are the main focus of doctors specialising in maternal-fetal medicine.
Serious pre-existing disorders which can reduce a woman's physical ability to survive pregnancy include a range of congenital defects and diseases acquired at any time during the woman's life.