Pregnancy on Contraception

Pregnancy during contraceptive use is method failure or incorrect use. Typical use failure in the first year per 100 women is 0.05 for implants, 0.2 for the levonorgestrel intrauterine device, 0.8 for the copper T 380A, 3 for progestin-only injectables, 8 for combined pills and 2 for the lactational amenorrhoea method used for 6 months. The clinician must confirm and locate the pregnancy, exclude ectopic pregnancy, deal with the method, and provide care in line with the law and the patient’s decision.

Causes. Missed or late pills, vomiting or diarrhoea, interacting medicines, late injections, incorrect implant placement or expiry, intrauterine device expulsion, perforation or malposition, pregnancy already present at the time of starting the method, and incorrect use of barrier or fertility awareness methods.

History. Date of last menses, method and timing, missed doses, vomiting, medicines, unprotected sex and emergency contraception, symptoms of pregnancy and of ectopic pregnancy, breastfeeding status.

Examination. Vital signs, abdominal and bimanual examination, speculum examination for intrauterine device threads.

Confirm pregnancy. Urine or serum hCG, followed by ultrasound where available to date and locate the pregnancy.

Exclude ectopic pregnancy. With an intrauterine device, a progestin-only method or after sterilisation, the proportion of ectopic pregnancies is higher. Use ultrasound, or careful clinical monitoring when ultrasound is not available.

Locate the device. Confirm whether an intrauterine device is in the uterus by threads or ultrasound. If it is not located, it may have been expelled or perforated.

Differential diagnosis. Intrauterine pregnancy, ectopic pregnancy, miscarriage in progress, molar pregnancy, and non-pregnant causes of a positive test and amenorrhoea.

Stop or remove the method.

• Combined pill, progestin-only pill, injectable, patch or ring: stop. There are no known risks to the foetus.
• Implant: remove or refer for removal. There are no known risks to the foetus conceived with an implant in place.
• Intrauterine device with threads visible or retrievable in the first 3 months: remove by gently pulling the threads, and advise return for heavy bleeding, cramping, pain, abnormal discharge or fever.
• Intrauterine device with threads not visible: ultrasound. If the device is in the uterus, the patient may continue the pregnancy and seek care promptly for bleeding, cramping, pain, discharge or fever. If the device is not located, it may have been expelled.

Risks of a retained device. Miscarriage, preterm birth and infection are more likely when the device remains in place, which is why removal is advised when the threads are accessible.

Pregnancy options. Offer antenatal care or other options in line with the law. Explain the options without judgement and respect the decision.

Postabortion or postpartum contraception. Offer a method before discharge.

Review of the failure. Identify the cause and correct it before choosing the next method.

Emergency situations. If pain, bleeding or faintness, assess urgently for ectopic pregnancy.

Follow up. Antenatal booking for continuing pregnancies. Review within 2 weeks after any pregnancy loss or termination for method choice.

Method decisions. Choose a more reliable method where the cause was user dependent, such as an implant, intrauterine device or injectable. Resolve any interaction by switching method or adding a backup.

Referral and escalation. Refer suspected ectopic pregnancy, a retained device with bleeding or sepsis, pregnancy with a displaced or unlocated device, and patients requiring termination services beyond local capacity.