Pregnancy (not a disease)
Overview
Watch Pregnancy – Overview |
Physiological Changes in Pregnancy
Uterus, Vagina and Breast Physiology changes
Uterus (Cervix + Isthmus + Body of uterus)
- Muscle hypertrophy til 20weeks then stretching till term.
- Uterine and ovarian arteries undergo hypertrophy
- Cervix
- Reduced collagen → allows dilatation
- Hypertrophy of cervical glands → thick mucus plug
- Uterine body
- ↑size, shape, shape and consitency
- Increases 10-fold
Vagina
- ↑Oestrogen → stimulates glycogen synthesis and deposition in the vagina → lactobacilli proliferation → lactic acid production → decreases pH in the vagina preventing pathogenic bacterial growth
Breast
- ↑Oestrogen → Fat tissue, lactiferous ducts
- ↑Progesterone → Breast lobule
Endocrine Physiology changes
Pituitary Gland
- Enlarges because of ↑anterior lob hormone secretion
Thyroid hormones
- Thyroid gland hypertrophy because of increase demand during pregnancy
Remember that iodine, antithyroid drugs or antibodies associated with thyroid disease can cross the placenta and affect the fetal thyroid function |
Endocrine changes
- ↑Progesterone
- ↑Oestrogen (mainly oestradiol)
- ↑Human placental lactogen
Progesterone
- Causes smooth muscle relaxation
- Reflux
- ↑Tidal volume of lungs
- Prevents preterm labour (because it relaxes the uterus)
Oestrogen
- Promotes breast and nipple growth
- Increases uterine blood flow, myometrial growth and cervical softening
- Increases sensitivity of myometrial oxytocin receptors
Human placentala lactogen
- Modifies maternal metabolism → ↑energy supply to the featus
- ↑Insulin secretion but ↓insulin peripheral effect, promoting glucose supply to the infant.
Haemtological Physiology Changes
- ↑Plasma volume (~40%) – acute weight gain is commonly due to oedema
- ↑Red cell volume
- ↑WBC – neutophilia specifically
- Slight ↓platelets
- ↑Clotting factors → hypercoagulable state
Respiratory Physiology Changes
- Uterus grows → diaphragm rises → breathing becomes diaphragmatic
- ↑Tidal volume (~40%)
Cardiovascular Physiology Changes
- ↑Cardiac output
- ↑Heart Rate (15bmp) × ↑Stroke Volume (~10%)
- ↓Peripheral resistance
- Blood pressure (most noticeable diastolic) drop by ~15mmhg by mid-term and return back to normal full term.
Urinary Physiology Changes
- ↑Kidney size by 1cm
- ↑ Renal blood flow (~40%) a result of increase cardiac output.
- ↑ Renal blood flow means ↑ GFR
Digestive Physiology changes
- ↑Progestrone → Oesophageal sphincter relaxation → oesophageal reflux
- ↑Progestrone → reduced bowel motility → constipation
- Uterine enlargement → Increase intra-abdominal pressure → worsens reflux + heart burn
Watch Video Physiological Changes during Pregnancy |
Signs and Symptoms
Early Pregnancy
- Amenorrhoea
- Nausea/vomiting – 2/3 of women (morning sickness)
- Breast tenderness and enlargement
- Increased urinary frequency
- Pigmentation of areola
- Dyspnea
- Fatigue
- Light headedness
Late Pregnancy
Hormonal changes
- Nausea and Vomiting
- Gastro-oesophageal reflux (Progesterone)
- Constipation (Progesterone)
- Breast enlargement
- Vaginal discharge
Uterine Enlargement
- Pelvic discomfort
- Backache
- Siatica
- Stress incontinence (3rd trimester)
- Haemorrhoids (3rd trimester)
Other
- Carpal tunnel syndrome
- Polyuria
- Itching and rash
- Headaches
- Dyspnea
- Fatigue
- Insomnia
- Stretch marks
- Calf cramps
- Braxton Hicks contractions
Remember Urinary infections are common in pregnancy. Screen for UTIs! |
Diagnosis
Any of the following:
- Beta-hcG in urine or blood (most common)
- Positive ultrasound examination of abdomen
- Fetal cardiac activity on Doppler ultrasound
Supported by:
- Amenorrhoea
- Clinical evidence
Side note ß-hCG is produced by synctiotrophoblast (outside of blastocyst that invades into uterine wall – implantation). ß-hCG prevents degeneration of the corpus luteum (and therefore can continue producing progesterone until placental progesterone can take over at about 6 weeks). B-hcG concentration doubles every 48 hours during first 30-40 days after implantation of a viable, intrauterine pregnancy. After which it slowly rises approximately to 10 weeks then declines until reaching a plateau in 2 nd and 3 rd trimester. |
Remember Causes of slow rise in B-hCG: ectopic pregnancy, miscarriage (not possible to detect off single level – must do multiple tests) |
Remember Causes of fall in B-hCG: can be physiological if at 10 weeks but mainly consistent with resolving ectopic, miscarriage |
Antenatal Check
Antenatal check refers to the health care provided to a pregnancy woman throughout pregnancy until labour. Basically a screening program intended to detect complications early, provide health education and implement effective health promotive and preventative interventions.
TIMING (4:2:1)
- 4 weekly till 28 weeks
- 2 weekly from 28 – 34 weeks
- Weekly from 36 till delivery
Normal, uncomplicated pregnancy
- First visit (discussed in detail in next section)
- First ultrasound
Remember Role of ultrasounds: 1st trimester – Determining viable pregnancy versus miscarriage, incomplete miscarriage, molar pregnancy and ectopic pregnancy, Dating scan, Screening (Nuchal fold thickness) and fetal anatomy. 2nd trimester – Fetal anatomy, Fetal measurements, Placental location, Sex of baby (if parents want to know) |
Indications for Ultrasound during pregnancy |
Routine antenatal check |
Antepartum Haemorrhage |
Fundal height is small or large for dates |
Medical complications of pregnancy – diabetes, Preeclampsia |
Abnormal foetal presentation |
Unstable lie at term |
Placental location if previous scans show LLP |
First Visit to Doctor
Introduction: Confirmation of pregnancy and discussion of models of care
- Establish if planned pregnancy – Affects potential decision for abortion and how the woman will deal/approach pregnancy
- Demographics (age, ethnicity)
- Date of the first day of LMP and thus expected date of delivery
- Use Naegele’s rule, based on 280-day average for each pregnancy i.e. add 9 months and 7 days.
- Importance of dating: antenatal schedule is evidence based and involves tests done at particular times so gestational age should be as accurate as possible.
- Ultrasound sounds also do dating
- Important to keep in mind that Indian or Afro-Caribbean women have shorter gestational times than Caucasians
Naegele’s rule (Nagel’s rule) predicts an estimated due date based on the woman’s last menstrual period. |
- Current antenatal history – common symptoms of early pregnancy
- Obstetric history
- Important since previous problems increase the chance of reccurence (e.g. gestational diabetes, pre-eclampsia, miscarriage etc.)
- To establish: previous antenatal/intrapartum/post-partum problems: miscarriages, ectopics, stillbirths, live births, mode of delivery, induction or spontaneous, gestation
- Gravidity and parity (G.P.)
- Breast feeding history – Benefits: better nutrition, GI function, immunological protection, psychological well-being for mother, long term benefits for child
- Gynaecological history
- Date of last pap smear and result
- Previous contraception use
- Gynaecological problems – endometriosis, PID, ovarian cysts, fibroids
- Medical history
- Surgeries
- Medications (inc. vitamins, folate, iodine supplementation)
- Medical conditions (e.g. hyperlipidemia, epilepsy, Graves etc.)
- Allergies
- Immunisation status
- Social History
- Psychosocial support (grandparents will be around? Partner? Financial situation?)
- Smoking
- Alcohol
- Nutrition
- Physical exercise (recommended, but not excessive)
Remember Smoking is associated with premature birth, placental abruption, miscarriage, low birth weight, still birth, placenta previa |
Remember With Alcohol there is no safe level during pregnancy however 2 standard drinks per day not associated with any adverse pregnancy outcomes. High levels associated with Fetal Alcohol Syndrome |
- Family history – E.g. congenital conditions (heart defects), syndromes (e.g. Down syndrome), cystic fibrosis etc.
Examination
- General Observations
- BMI
- Vital signs
- Cardiovascular exam
- Thyroid exam
- Breast exam
- Abdominal exam
- Vaginal Exam
- Urinalysis
Remember risk of UTI increases during pregnancy |
Investigations
- ABO
- Rhesus
- FBC
- Rubella
- TPHA
- Hep B and Hep C
- HIV
- Syphilus
- Urine M/C/S
- Ultrasound
Medical Complications During Pregnancy
- Hyperemesis Gravidarum
- Gestational Diabetes
- Thromboembolic disorder
- Anaemia
- Hypertension
- Pre-eclampsia
- PV Bleeding
- Ante-partum haemorrhage
More info Medical Complication During Pregnancy
Unplanned Pregnancy
Contraception