The Chemical Discovery Behind the First Oral Contraceptive Pill
A 1952 patent for a synthetic hormone that became the active ingredient in the first effective oral contraceptive pill.
Original patent title: “delta 4-19-nor-17alpha-ethinylandrosten-17beta-ol-3-one and process”
A 1952 patent for a synthetic hormone that became the active ingredient in the first effective oral contraceptive pill. Granted to Syntex SA in 1956 with 1 claim and 19 forward citations, and it is now in the public domain.
Key facts
Coverage
What does this patent actually cover?
The patent describes the chemical synthesis of a specific steroid compound known as 19-nor-17alpha-ethinyltestosterone, later called norethindrone. By removing a carbon atom from the standard testosterone structure and adding an ethinyl group, the inventors created a molecule that remains stable and active when taken orally. This compound mimics the body's natural progesterone, effectively suppressing ovulation to prevent pregnancy.
The gap
What does this patent NOT cover?
- Does not cover the final pharmaceutical delivery mechanism or pill formulation.
- Does not cover other synthetic progestins developed after this specific chemical structure.
- Does not cover the medical method of using the compound for contraception.
These exclusions are unique to PatentBrief — derived from the actual claim language, not patent-office boilerplate.
What made this novel
The inventors realized that removing the C-19 methyl group from the testosterone molecule significantly increased its potency when ingested, overcoming the problem of the liver breaking down hormones before they could reach the bloodstream.
Schematic visualization of the patent's claim structure. Hand-drawn diagrams in progress for each landmark patent.
Where you've seen this
Real-world examples
Norethindrone-based oral contraceptives
Hormone replacement therapy medications
Why it matters
The bigger picture
This discovery transformed reproductive health and social structures in the 20th century. It provided the chemical foundation for the birth control pill, which allowed women unprecedented control over their reproductive lives and fundamentally changed global labor markets and family planning.
Filed
November 12, 1952
Granted
May 1, 1956
Market context
Who's building on this
Companies in this space
Pharmaceutical giants like Pfizer, Bayer, and various generic drug manufacturers continue to produce norethindrone-based medications. The foundational work by Syntex paved the way for the entire modern oral contraceptive market.
Market impact
This patent triggered the birth of the multi-billion dollar oral contraceptive industry. It moved reproductive health from a niche medical topic to a central pillar of global public health and pharmaceutical commerce.
Claim 1 — Plain English
What this patent covers
The patent describes the chemical synthesis of a specific steroid compound known as 19-nor-17alpha-ethinyltestosterone, later called norethindrone. By removing a carbon atom from the standard testosterone structure and adding an ethinyl group, the inventors created a molecule that remains stable and active when taken orally. This compound mimics the body's natural progesterone, effectively suppressing ovulation to prevent pregnancy.
The clever bit
The inventors realized that removing the C-19 methyl group from the testosterone molecule significantly increased its potency when ingested, overcoming the problem of the liver breaking down hormones before they could reach the bloodstream.
What it does not cover
- Does not cover the final pharmaceutical delivery mechanism or pill formulation.
- Does not cover other synthetic progestins developed after this specific chemical structure.
- Does not cover the medical method of using the compound for contraception.
Patent Journey
From filing to expiry
PatentBrief Score
Impact Score
Early stage
Citation count
26/40
Moderately cited
Claim breadth
1/20
Narrow claimsclaimsThe numbered statements at the end of a patent that legally define what the inventor owns.Read more →
Recency
0/20
Older than 20 years
Assignee scale
0/20
Independent or smaller assigneeassigneeThe entity that owns the patent — usually the inventor's employer or a company.Read more →
PatentBrief Impact Score — based on citation count, claim breadth, recency, and assignee scale. Not a legal assessment.
Heuristic Value Estimate
What this patent might be worth
$27K – $86K
Midpoint $54K · expired or expiring · industry ×3.0
Heuristic only — blends forward/backward citation counts, claim scope, time remaining, litigation history, and CPC-derived industry baseline. Real valuations need a professional appraisal.
The original legal language
Original claims
1 claim as filed with the patent office.
Concepts involved
Citations
Patent lineage
Cite this patent
Carl, D., Luis, M., & George, R. (1956). The Chemical Discovery Behind the First Oral Contraceptive Pill (U.S. Patent No. 2,744,122). U.S. Patent and Trademark Office. https://patentbrief.org/patent/us/2744122/birth-control-pill-norethindrone
Auto-generated from the patent record. Double-check author order and the issue date against the official USPTO document before submitting.
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Common Questions
Frequently Asked Questions
What does The Chemical Discovery Behind the First Oral Contraceptive Pill cover?
A 1952 patent for a synthetic hormone that became the active ingredient in the first effective oral contraceptive pill.
Who owns patent US 2744122?
Syntex SA owns this patent, granted in 1956.
When does this patent expire?
This patent has expired and is now in the public domain — anyone can use the invention freely.
What is patent US 2744122 cited by?
This patent has been cited by 19 later patents that build on its ideas.
What problem does this patent solve?
This discovery transformed reproductive health and social structures in the 20th century. It provided the chemical foundation for the birth control pill, which allowed women unprecedented control over their reproductive lives and fundamentally changed global labor markets and family planning.
What does this patent NOT cover?
Does not cover the final pharmaceutical delivery mechanism or pill formulation.
Patent monitoring