Obstetrics and gynaecology for PLAB 1

A 27 year old woman who is 9 weeks pregnant by dates has light vaginal bleeding and mild cramping for a day. She is haemodynamically stable. A transvaginal ultrasound shows an intrauterine gestational sac with a fetal pole and a heartbeat, and the cervical os is closed on speculum. She is rhesus positive. What is the SINGLE most likely diagnosis?

1. Cervical polyp Painless bleeding from a small growth (polyp) visible at the opening of the womb. It is found by examining with a speculum rather than on a scan. It does not fit a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks.
2. Molar pregnancy Heavy bleeding with a womb that is bigger than expected for the number of weeks, severe vomiting (hyperemesis), and a very high hCG level. The scan shows a pattern like a snowstorm. Here, a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks points elsewhere.
3. Ectopic pregnancy Pain on one side with bleeding, and an empty womb on the scan despite a positive pregnancy test. This is the diagnosis that kills, so it must be ruled out before anything is called a miscarriage. But a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks does not point to it.
4. Cervical ectropion Painless spotting after sex, with a cervix that bleeds easily when examined with a speculum. This is common in pregnancy and does not threaten it. That does not match a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks.
5. Threatened miscarriage correct Correct. Bleeding with a closed opening of the womb, and a living pregnancy inside it. Around three out of four of these pregnancies carry on, and the bleeding itself does not change that.

The point: Bleeding before 12 weeks means this is a pregnancy of unknown location until a scan shows otherwise, and ectopic pregnancy is the one diagnosis you must not miss. If the opening of the womb (cervical os) is open and pregnancy tissue is passing, this is an inevitable or incomplete miscarriage. If the opening is closed and the baby is still alive, this is a threatened miscarriage. The first choice, when the woman is stable and has no infection, is watching and waiting (expectant management) for 7 to 14 days. If that does not work, or she does not want to wait, drug treatment (medical management) or surgery follows. Anti-D is given after surgery, and after any bleeding from 12 weeks onwards, in a woman with rhesus negative blood. It is not needed for a threatened miscarriage before 12 weeks if no instruments were used.

Source: NICE NG126 — Ectopic pregnancy and miscarriage: diagnosis and initial management NICE · tier 1, national regulator or guidance

A 27 year old woman who is 9 weeks pregnant by dates has light vaginal bleeding and mild cramping for a day. She is haemodynamically stable. A transvaginal ultrasound shows an intrauterine gestational sac with a fetal pole and a heartbeat, and the cervical os is closed on speculum. She is rhesus positive. What is the SINGLE most appropriate immediate management?

1. Vaginal misoprostol A drug (misoprostol) put into the vagina, used when watching and waiting has failed or is not wanted. A repeat pregnancy test at three weeks confirms it has worked. But a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks does not point to it.
2. Anti-D immunoglobulin For a woman with rhesus negative blood who is having surgery, and for any bleeding from 12 weeks onwards. Not needed for a threatened miscarriage before 12 weeks if no instruments were used. It does not fit a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks.
3. Remove products from the cervical os with sponge forceps Taking pregnancy tissue out of the cervical opening with special forceps. This treats cervical shock: tissue stretching the opening causes a slow heart rate and low blood pressure through the vagus nerve, and this gets better the moment the tissue is removed. Here, a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks points elsewhere.
4. Expectant management for 7 to 14 days Watching and waiting (expectant management) for 7 to 14 days. This is the first choice for a stable woman with no infection and no heavy bleeding, and it works for most women without any treatment. That does not match a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks.
5. Reassure and offer a follow-up scan in one week correct Correct. No treatment improves the outcome of a threatened miscarriage. Progesterone is only considered when there is a history of previous miscarriage, which she does not have.

The point: Bleeding before 12 weeks means this is a pregnancy of unknown location until a scan shows otherwise, and ectopic pregnancy is the one diagnosis you must not miss. If the opening of the womb (cervical os) is open and pregnancy tissue is passing, this is an inevitable or incomplete miscarriage. If the opening is closed and the baby is still alive, this is a threatened miscarriage. The first choice, when the woman is stable and has no infection, is watching and waiting (expectant management) for 7 to 14 days. If that does not work, or she does not want to wait, drug treatment (medical management) or surgery follows. Anti-D is given after surgery, and after any bleeding from 12 weeks onwards, in a woman with rhesus negative blood. It is not needed for a threatened miscarriage before 12 weeks if no instruments were used.

Source: NICE NG126 — Ectopic pregnancy and miscarriage: diagnosis and initial management NICE · tier 1, national regulator or guidance

A 27 year old woman who is 9 weeks pregnant by dates has light vaginal bleeding and mild cramping for a day. She is haemodynamically stable. A transvaginal ultrasound shows an intrauterine gestational sac with a fetal pole and a heartbeat, and the cervical os is closed on speculum. She is rhesus positive. What is the SINGLE most appropriate advice to give?

1. This was not caused by anything you did correct Correct. She will be quietly going over in her head what she did last week. Saying this before she asks is the part of the visit she will remember.
2. One miscarriage does not mean the next pregnancy is at risk Around one in five known pregnancies ends in loss. Tests are offered after three losses, or after two losses above 12 weeks. That does not match a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks.
3. You will be offered a scan early in the next pregnancy A reassurance scan at six or seven weeks is routine after a loss. Knowing this is available changes how the next pregnancy feels. It does not fit a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks.
4. Nothing in the vagina until the bleeding stops This lowers the risk of infection while the opening of the womb is still open. It is easier to follow as a clear instruction than as a vague warning. Here, a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks points elsewhere.
5. Come back urgently for heavy bleeding, fever or offensive discharge The specific warning signs to watch for, for heavy bleeding and for infection of the womb lining, rather than a vague instruction. But a closed opening of the womb with a fetal heartbeat on the scan at 9 weeks does not point to it.

The point: Bleeding before 12 weeks means this is a pregnancy of unknown location until a scan shows otherwise, and ectopic pregnancy is the one diagnosis you must not miss. If the opening of the womb (cervical os) is open and pregnancy tissue is passing, this is an inevitable or incomplete miscarriage. If the opening is closed and the baby is still alive, this is a threatened miscarriage. The first choice, when the woman is stable and has no infection, is watching and waiting (expectant management) for 7 to 14 days. If that does not work, or she does not want to wait, drug treatment (medical management) or surgery follows. Anti-D is given after surgery, and after any bleeding from 12 weeks onwards, in a woman with rhesus negative blood. It is not needed for a threatened miscarriage before 12 weeks if no instruments were used.

Source: NICE NG126 — Ectopic pregnancy and miscarriage: diagnosis and initial management NICE · tier 1, national regulator or guidance