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Birth Control Pill Generations: How Should You Choose Between Them?

The differences in ingredients between generations of oral contraceptive pills, and the blood clot risk factors to check first when choosing one.

Published 2026-10-14 Updated 2026-10-14 Reviewed by Seeun Cho, Medical Director · Obstetrics & Gynecology Specialist

When choosing an oral contraceptive pill, the terms 2nd generation and 3rd generation come up first. It is easy to assume that a higher number means a better pill, but a generation is not a performance ranking; it is the order in which the progestin ingredient has changed. What should be checked first is not the generation number but smoking, age and existing medical conditions.

This column sets out in turn the differences in ingredients by generation, the burdens each has reduced and those that remain, and the risk factors to look at first when choosing.

01

What divides oral contraceptive pills into generations?

Key point
The generation of an oral contraceptive pill is not a ranking of effectiveness but is set by the type of progestin it contains. Combined oral contraceptives are made of two hormones, oestrogen and progestin, and depending on which progestin is used they are classed as 2nd, 3rd or 4th generation.

Combined oral contraceptive pills are made of two hormones, oestrogen and progestin, and the generations are divided according to which ingredient the progestin is made from. Oestrogen thickens the uterine lining and sends signals that prepare for ovulation, while progestin suppresses ovulation and makes cervical mucus sticky.

Each new generation aimed to reduce the drawbacks of the one before, but because the ingredients changed in a way where easing one burden increased another, it is hard to say that a later generation is better in every respect. The generations are not a ranking table but the order in which the ingredients have changed.

  • 2nd generation — uses levonorgestrel as the progestin and is known to carry a relatively low cardiovascular burden
  • 3rd generation — uses desogestrel or gestodene and was developed to reduce the burden of acne and hirsutism
  • 4th generation — uses drospirenone, cyproterone acetate or dienogest and has advantages in easing swelling and acne
Anatomy illustration related to Birth Control Pill Generations: How Should You Choose Between Them?
02

What has each generation reduced, and what burdens remain?

Key point
The 1st generation had a high oestrogen content and carried a heavy burden, which is why no product of that generation is currently approved in Korea. The 2nd to 4th generations each share three factors, cardiovascular burden, acne and hirsutism, and blood clot risk, in different proportions.

The 1st-generation oral contraceptive pill had a high oestrogen content and carried a heavy burden; as the 2nd, 3rd and 4th generations were developed in turn, no 1st-generation product remains approved in Korea. The 2nd generation carries a low cardiovascular burden but can cause acne and hirsutism, while the 3rd generation reduced that burden but comes with reports of a slightly higher blood clot risk.

The 4th generation has advantages in easing swelling and acne, but because its blood clot risk is the highest it is classed as a prescription-only medicine, whereas the 2nd and 3rd generations can be bought at a pharmacy. With any generation, reducing one burden leaves another behind.

03

What risk should be checked first when choosing a pill?

Key point
When choosing an oral contraceptive pill, the first thing to look at is not the generation number but the risk of blood clots. Because oestrogen makes the blood stickier, the risk of blood clots rises slightly while taking the pill, whatever the generation, and the burden grows further when other conditions overlap.

The oestrogen in oral contraceptive pills tends to make the blood stickier than usual, so taking the pill raises the risk of blood clots slightly, whatever the generation. The burden becomes greater when factors overlap, such as smoking, being over 35, having liver disease, or having had blood clots or cardiovascular disease in the past.

Smokers over 35 are classed as people who should not take oral contraceptive pills, so other methods of contraception need to be discussed. If, while taking the pill, the calf becomes swollen and painful, or there is shortness of breath or tightness in the chest, it should be checked by a doctor straight away rather than endured.

  • Smoking — smoking raises the risk of blood clots further
  • Over 35 — the risk of blood clots rises with age
  • Liver disease — having liver disease increases the burden of processing hormones
  • History of blood clots or cardiovascular disease — having had them before adds to the risk
Doctor's view

How the doctor decides

Seeun Cho, Medical Director · Obstetrics & Gynecology Specialist

I do not choose a pill by its generation number alone

I do not decide that a pill is good or bad just by looking at its generation number. A generation is simply the order in which the progestin ingredient has changed, so a later generation cannot be considered better in every respect. That is why, in the consultation room, I look first at whether the ingredient suits the patient's current condition and whether she has had trouble with that ingredient before, rather than at which generation it is.

I check smoking and age first

Before prescribing, I first check whether the patient smokes and how old she is. Oestrogen makes the blood stickier and can raise the risk of blood clots regardless of generation, and smokers over 35 should not take the pill. So if these conditions apply, I do not simply recommend an oral contraceptive pill but discuss other methods of contraception with the patient.

I also consider existing conditions and past experience

I also check whether the patient has had liver disease, blood clots or cardiovascular disease. With such conditions the burden can be greater even within the same generation, so I do not simply recommend an ingredient because it is popular. I also ask in advance whether she has ever had a swollen, painful calf or shortness of breath, and I decide the direction of the prescription based on her answer.

Summary

In summary

A higher generation does not automatically make an oral contraceptive pill a better one; each generation carries cardiovascular burden, acne and hirsutism, and blood clot risk in different proportions. What should be checked first is not the generation number but smoking, age and existing conditions, and smokers over 35 are advised not to take the pill. If the calf becomes swollen and painful, or breathing becomes short and the chest feels tight, it should be checked by a doctor without delay.

FAQ

Frequently asked questions

QIs a higher-generation oral contraceptive pill a better pill?
A

No. A generation does not indicate a performance ranking but the order in which the progestin ingredient has changed. In later generations some burdens have been reduced while others have increased, so it is hard to say they are better in every respect.

QCan the 2nd, 3rd and 4th generations all be bought at a pharmacy?
A

The 2nd and 3rd generations can be bought at a pharmacy, but the 4th generation is classed as a prescription-only medicine. Blood clot risk is known to be highest with the 4th generation, which is why it is available only on prescription.

QIs it impossible to take oral contraceptive pills after the age of 35?
A

Age alone does not rule out taking the pill, but smokers over 35 are classed as people who should not take it. In such cases it is safer to discuss other methods of contraception with a doctor.

Medical review
Seeun Cho, Medical Director · Obstetrics & Gynecology Specialist
This content is general medical information and may not apply to every individual. Diagnosis and treatment are decided through a consultation.