Continuous electronic fetal monitoring

Continuous electronic fetal
monitoring in labour by cardio-tocography (CTG) is now the accepted standard for intra-partum fetal monitoring in women with additional risk factors.

    Compared to intermittent auscultation, CTG is associated with:

    1. A halving of the risk of neonatal seizures.
    2. A significant increase in the risk of caesarean section (relative risk 1.66; 1.30 – 2.13)
    3. A significant increase in the risk of instrumental delivery (relative risk 1.16; 1.01 – 1.32)
    4. No significant difference in overall perinatal death rate
   5. No significant difference in the risk of cerebral palsy

These results remain true for low-risk, high-risk and preterm pregnancies and were unaffected by access to fetal blood sampling.

Muscles of anterior abdominal wall (1)

Laterally the anterior abdominal wall consists of 3 separate sheet-like layers of muscles
1. External oblique muscle (outer layer)
2. Internal oblique muscle (intermediate layer)
3. Transversalis abdominis muscle (inner layer).

They become aponeurotic anteriorly, fuse and form the sheath around the rectus abdominis muscles.

Above the umbilicus, the anterior rectus sheath is formed by external oblique aponeurosis and internal oblique aponeurosis. Posterior rectus sheath is formed by aponeuroses of transversus abdominis and internal oblique muscles.

Inguinal ligament

The inguinal (Poupart's) ligament extends from the anterior superior iliac spine to pubic tubercle.
It is the free lower boder of the external oblique aponeurosis.
It is rolled inwards inferiorly into a gutter which forms the floor of the inguinal canal.

Gluteus maximus muscle

The prominent muscle of the buttock.
Is supplied by the inferior gluteal nerve.
Powerful lateral rotator and extensor at the hip joint.
Extends and stabilizes the knee joint.

Mongolian blue spot (photo)

Mongolian blue spot

Mongolian spots are flat, blue, or blue-gray skin markings near the buttocks that commonly appear at birth or shortly thereafter.
Mongolian blue spots are common among those who are of Asian, East Indian, and African descent.
Mongolian spots are not associated with disease. The markings may cover a large area of the back.

Occasionally, Mongolian blue spots are mistaken for bruises. It is important to recognize that Mongolian blue spots are birthmarks, NOT bruises.

Characteristic features are
    1.Blue or blue-gray spots on the back, buttocks, base of spine, shoulders, and other body areas
   2.Flat area with irregular shape and unclear edges
    3.Normal skin texture
    4.The spots are usually 2 - 8 centimeters wide.
No treatment is necessary or recommended.
The spots often fade in a few years and are almost always gone by adolescence.

Alternative Names
(Mongolian spots; Congenital dermal melanocytosis; Dermal melanocytosis)

Erythema toxicum

Erythema toxicum is a common rash usually seen in newborns. Usually appears on 2nd or 3rd days. It takes the form of a white pinpoint head on an oval erythematous base. Histological features show massive numbers of oesinophils. The rash rarely lasts for more than a few days and is harmless.
Erythema toxicum may appear in 50 percent or more of all normal newborn infants.
Its cause is unknown.
The condition may be present in the first few hours of life, generally appears after the first day, and may last for several days.
Alternative Names (Erythema toxicum neonatorum)

Doppler ultrasound and the prediction of adverse pregnancy outcomes

Uterine artery doppler can be done during the first and early second trimester to predict pregnancies at risk of adverse outcomes. Sixty to 70% of women with bilateral uterine artery notches at 20-24 weeks gestation will develop one or more of complications (preeclampsia, FGR, or placental abruption).

Dating the pregnancy

Setting a reliable EDD is one of the important functions in AN care.
Precise dating is important in preterm gestations, prolonged pregnancies and a number of different screening tests.
The EDD can be calculated from the first day of LMP by adding 7 days and 9 months. However, this method assumes menstrual cycle to be 28 days cycle with ovulation on day 14 and the woman must remember her LMP accurately. In reality, most women have not 28 days cycles and the timing of ovulation is variable within a cycle. Menstrual dates are not accurate in 25-40% of women.
Dating by an ultrasound scan in the first trimester must be done ideally between 10 and 14 weeks, and EDD set by this scan should be used in preference to menstrual EDD.
CRL crown rump length is used up until 13weeks+6days with accuracy ±4days.

Thyroid function in pregnancy

Human chorionic gonadotrophin (hCG) has the same alpha subunit as thyroid stimulating hormone (TSH). Maternal TSH production is suppressed during the first trimester, when hCG levels are the highest. The TSH response to TRH (thyrotrophin releasing hormone) is reduced during the first trimester then returns to normal after this. Total T3 and T4 production increase because of the increased production of thyroid binding globulin (TBG) which starts in the first 2 weeks and reaches plateau by 20 weeks. Thyroid hormone reference ranges for nonpregnant women are not appropriate in pregnancy. Trimester specific range of free T4, free T3 and TSH should be analysed. There is a fall in TSH and a rise free T4 concentrations in 1st trimester followed by fall in fT4 concentration with advancing gestation. Iodine is essential for thyroid hormone synthesis. There is increased renal loss of iodide in pregnancy. The thyroid compensates by increasing uptake of iodide from circulation. Thyroid gland becomes enlarged where there is background iodine deficiency.

Ventilation in pregnancy

Ventilation begins to increase significantly around 8 weeks of gestation.
Mechanical aspects of ventilation alter significantly in pregnancy.
Tidal volume increases about 40% (from 500ml to 700ml). The respiratory rate remains unchanged. Therefore the minute ventilation (the amount of air in and out of the lungs within one minute) increases. That minute volume is the product of tidal volume and the respiratory rate. It increases by approximately 30-50% with pregnancy.
Pregnant women perceive this increase in minute volume as shortness of breath, which affects 60-70% of pregnant population.
Expiratory reserved volume and residual volume both decrease in pregnancy. The sum of these two, the functional residual capacity, decreases about 10-25%. FRC is further reduced in supine position.
Forced expiratory volume in one second FEV1 and peak expiratory flow rate remain unchanged.

Haemostasis and coagulation in pregnancy

Pregnancy is a hypercoagulable state.
Almost all procoagulant factors, including factors VII, VIII, IX, X, XII, and fibrinogen, are increased.
Fibrinogen is increased by 50% (from 300mg/dL to 450mg/dL).
Von Willebrand factor also increased.
Protein S activity decreases.
Activated protein C resistence increased.
Antithrombin III levels remain  unchanged.
Plasma homocystiene concentration are lower in normal pregnancies.
Maternal plasma D dimer concentration increases progressively from conception until delivery.
Incidence of venous thromboembolic complications is five time greater during pregnancy.